The North American Species of Crepidotus
5. Crepidotus parvulus Murr., Mycologia 5: 27. 1913.
Illustration: Fig. 38.
Pileus 1-4 mm broad, resupinate, at first orbicular-reniform, becoming conchiform and convex, pure-white, dry, densely floccose-pulverulent, margin even. Context thin, soft.
Lamellae radiating from an eccentric point, rounded behind, white to yellowish-ochraceous, broad, distant, thin.
Spores 4-5.3 µ in diameter, globose, conspicuously punctate or echinulate, pale yellow to pallid in KOH. Basidia 16-20 x 4-6 µ, 4-spored. Pleurocystidia rare, similar to cheilocystidia; cheilocystidia 24-27 x 4-7 µ, cylindric-clavate with irregular knob-like processes over the surface. Gill trama subparallel to slightly interwoven, hyphae 2.5-5 µ broad. Pileus trama homogeneous, interwoven. Cuticle a trichodermial turf, the hyphae thick-walled, colorless, branched, loosely arranged, 3-6 µ, broad. Clamp connections none on the epicuticular hyphae, rarely at the base of the basidium.
Habit, Habitat, and Distribution: On dead orange branches, Jamaica, October-November.
Material Studied: JAMAICA: Earle 334, the type (NY), from Hope Gardens, Oct. 20-Nov. 24, 1902.
Observations: Material of the type is meager. Although this species has been regarded as the same as C. quitensis (Singer, 1947), the latter differs from C. parvulus in the presence of clamp connections and slightly larger spores. The description of macroscopic characters above is taken from Murrill (1913), and that of microscopic characters is based on a study of the type.